Question: If $x \dagger y = x+3y$ and $x \oplus y = 2x^{2}-y^{2}$, find $(-4 \oplus -5) \dagger -3$.
First, find $-4 \oplus -5$ $ -4 \oplus -5 = 2(-4)^{2}-(-5)^{2}$ $ \hphantom{-4 \oplus -5} = 7$ Now, find $7 \dagger -3$ $ 7 \dagger -3 = 7+(3)(-3)$ $ \hphantom{7 \dagger -3} = -2$.